The blow tube can be a tube with an outside diameter the same as the inside diameter as your carboy neck. This allows you to just push that large diameter hose into the carboy neck and let it hang down into StarSan water in a bucket or blow. The open end of the tubing should be about 2" below the surface of the StarSan water.
You will not have this approximatley 1.5 inch tubing clog, which is the advantage.
The drawback to this is that as it blows off, it's taking potential beer out with the krausen, so you end up with less volume. I've lost as much as a half gallon of beer through my blow off tube. My solution is an 8 gallon bucket fermenter (with a standard airlock) for 5 gallon batches. I've never had one make it up to the airlock and clog or force the airlock out when I had all of this headspace.
Headspace usually equals oxygen that can cause off flavors. But in this case, it isn't an issue, because during high krausen the yeast are creating a lot of CO2 which keeps the oxygen out. Once primary fermentation slows down to a crawl, it's probably a good idea to move the beer into a carboy with less headspace. However, I have left them in the large bucket and have never noticed off flavors due to the large headspace.